Hello all,
As you can see, i'm new here 🙂 My name is Matthias from switzerland. I'm a electronic fanatic since i was 6 years old and i like to repair everything that is broken (cars + electronics).
Now i have a strange Story here!
I have a Krell KSA-100 here that was sitting for 20 years disassembled in my basement. Now the customer decided to repair it after 20 years. Back in 2002, this amp was already deeing disassembled by another people and he brang it to me disassembled too. But now, i have no screws for the cover plate, the AMP-Blocks and for the driver boards to the AMP-Block. I have really no idea if i got these screws 20 years ago or not! Fact is, i can't find them. Since this Beast is from USA, they have all inch-screws and i'm a metric guy! I have absolutely no idea what the dimensions of the missing screws are! Does anybody can help me in this bizarre situation? 🙂 🤐
BR Matthias
As you can see, i'm new here 🙂 My name is Matthias from switzerland. I'm a electronic fanatic since i was 6 years old and i like to repair everything that is broken (cars + electronics).
Now i have a strange Story here!
I have a Krell KSA-100 here that was sitting for 20 years disassembled in my basement. Now the customer decided to repair it after 20 years. Back in 2002, this amp was already deeing disassembled by another people and he brang it to me disassembled too. But now, i have no screws for the cover plate, the AMP-Blocks and for the driver boards to the AMP-Block. I have really no idea if i got these screws 20 years ago or not! Fact is, i can't find them. Since this Beast is from USA, they have all inch-screws and i'm a metric guy! I have absolutely no idea what the dimensions of the missing screws are! Does anybody can help me in this bizarre situation? 🙂 🤐
BR Matthias
I only need the thread size, the length i can measure by myself.
- Top Cover-screws
- The 4 long bolts to fix the AMP-Block to the chassis
- The small screws to fix the Driver-PCB to the AMP-Block
Use vernier calipers to measure the internal diameter (ID) of the holes, then estimate the number of turns per inch (25.4 mm) of thread length and compare with a table of common, standard U.S. type threads. Alternatively, just look around in the case for similar size screws, try them in the holes and check if they fit, assuming the matching nuts are captive, i.e. attached to the chassis so they can't also have been lost. Then you can see and measure that external thread more easily.
All you need now is to specify a suitable standard length, head shape (countersunk, round or cheesehead) and slot or Phillips drive plus general material specification . (they are likely just plated steel). A hardware seller that supplies foreign threads should be able to do the rest if you can't simply identify and buy a small quantity of suitable US product online.
example table only - https://www.boltdepot.com/fastener-information/machine-screws/machine-screw-diameter.aspx
All you need now is to specify a suitable standard length, head shape (countersunk, round or cheesehead) and slot or Phillips drive plus general material specification . (they are likely just plated steel). A hardware seller that supplies foreign threads should be able to do the rest if you can't simply identify and buy a small quantity of suitable US product online.
example table only - https://www.boltdepot.com/fastener-information/machine-screws/machine-screw-diameter.aspx
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Change all of them to Metric, doesn't really matter.
And charge the owner rent, for storing it 20 years.
That will stop any argument about changed screws.
And charge the owner rent, for storing it 20 years.
That will stop any argument about changed screws.
That is right, we had somebody in Italy who wanted studs for American speakers, many posts later it turned out spark plug top nuts were proper.
But I would try to work around that too, if possible.
Using thinner and longer screws, for example. Or opening the nut cages and replacing them.
We are used to British threads here, Metric is the legal one here, and American threads are something quite different in terminology.
Confusing for me at least.
Your link was for American screws, which is helpful.
The thread proportions are different from British dimensions (diameter, thread profile, pitch etc.)
British nuts will not fit American screws for the most part.
But I would try to work around that too, if possible.
Using thinner and longer screws, for example. Or opening the nut cages and replacing them.
We are used to British threads here, Metric is the legal one here, and American threads are something quite different in terminology.
Confusing for me at least.
Your link was for American screws, which is helpful.
The thread proportions are different from British dimensions (diameter, thread profile, pitch etc.)
British nuts will not fit American screws for the most part.
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